They are obviously less developed than China, Russia or Japan. But their population is huge and it is relatively developed. They have 12 times the population of Japan, Japan should be 12 times more productive to match India. And 12 times more productive is A LOT MORE productive.
Being 10-20 times more productive per capita than India is not that hard for Japan, South Korea, and eventually China (it is still developing), due to the high quality of their human capital as opposed to Indian human capital quality.
For example, South Korea has a 3% global manufacturing share, Japan has 7.2%, and India has 3.3%. But now compare their population size. As neither one of them is famous for some special natural resources, this has to be human capital.
But, I agree that these East Asian societies are truly unmatched and exceptional in human capital and so many ordinary countries in the Global South will find it pretty hard to leapfrog over India's 1.4 billion people through productivity per capita.
But, here we come to another lesser-understood fact. India is not a real country historically. They are an artificial amalgamation of many historically separated kingdoms, cultures, societies, etc, made by the British colonialists for easier administrative control. Only somewhat sharing a common religion (just like Christians of Europe have the same religion, nothing special) and manufactured hatred for Muslims.
They are more like a continent (sub-continent) in this case, instead of a naturally unified historical nation, I look at them like that.
They are an entity similar to like if Latin America unified into a single country (this sounds pretty unrealistic, but that's what the British did for India). So, India will not have longevity in this form. Divisions will lead to a disintegration of this fake construct over time 100%.
Africa also had some amazing civilizations in various historical snapshots, just like India, so nothing special here either, they are closer to Africans than closer to anyone else (both in division and human capital).
Let's take the combined Latin American GDP and compare it to the Indian sub-continent GDP and you get $5.7 trillion against $3.47 trillion for Latin America (that's like 165% of Indian GDP). And that is with 1/3 of the Indian population.
They have two totally different language families (Indo-European in the North, Dravidian in the South, also you have this genetic divide), languages, language scripts, and alphabets (10-20 major writing systems, and even more major languages, which then further divide even more in dialects),
Even 40% of Hindi speakers have various sub-dialects between them. Whereas you take Latin America, the majority of people speak clear Spanish. I don't see why anyone thinks this form of India will go anywhere in the long run.
Thousands of ethnic groups, and hundreds of terrorist organizations. You see these thousands of political parties in India in this election clown show, they have no unified ubiquitous language like Iran, only friction, friction, friction, chaos, chaos, chaos.
India is I think the biggest, over-estimated joke in this form of history that could ever exist. I'm sorry but they are nothing truly important.
That India is relatively advanced in some things, for example they were able to land a moonlander recently. They also have manufacturing, some IT, etc.
That is all not good in comparison to their size, South Korea is massively over-achieving in comparison to them. Also, their "IT" is pretty much going to be replaced rapidly in the next few years thanks to various LLMs coming from the US.